The present invention relates to a water filtering and purifying apparatus. In particular, the present invention relates to a container having a water filtration and purifying system therein which operates at low pressures generated by manually squeezing the container.
Water filtration or purification systems are not new. Many large scale purifying systems have been developed in an attempt to combat the impurities, contaminants, and chemicals appearing to some degree, sometimes substantial, in most sources of drinking water. However, one does not always have access to water purified by a large scale purifier. Portable water filters and purifiers have been developed to allow a user to obtain clean water wherever that user may go. Many portable water purifiers include a granular activated carbon (GAC) filtration section in combination with an iodine resin purification system, a filtered inlet, and a straw-like mouth piece through which the water must be sucked. Such purifiers have been disclosed in U.S. Pat. No. 4,298,475 and U.S. Pat. No. 4,995,976. A problem with these purifiers is that a user must exert a rather large sucking action to the straw to achieve flow through the GAC and the iodine resin, and a light headed condition may often result.
Pumping systems which use replaceable filters share a common problem in many instances of having to replace the filters often. In such pumping systems, debris from the pumped liquid, typically water, is trapped in the filter and rapidly clogs the filter, making it necessary that the filter be replaced.
Cartridge based water filtration and purifying systems are also known in the art. Magnusson, U.S. Pat. No. 5,273,649 discloses a disposable cartridge based water filtration device. Magnusson discloses a container having a filtration device therein. The filtration device in Magnusson has a common problem that many filtration devices in containers have, that is, it takes a full squeeze of the container to get liquid up to the nozzle, with very little water being ejected from the nozzle. Releasing the container from that squeeze before squeezing again reduces the pressure in the container below atmosphere causing the liquid in the nozzle to flow back into the container, thus forcing liquid back out of filtration device. This sequence of events is repeated with each squeeze and release of the container with very little water coming from the nozzle, making drinking very tiresome.